Protecting pedestrians and bicyclists: some observations and research opportunities

Pedestrians and bicyclists are commonly referred to as “vulnerable road users,” because in collisions with motor vehicles the lack of a protective structure and differences in mass heighten their injury susceptibility. Protecting them is a challenge, because road systems typically have been built for motor vehicles, with little attention to those on foot or on bicycles who may wish to travel on or alongside roads, or cross them, or change direction at intersections.